TY - GEN
T1 - Control of the discharge path in adhesive for separation of the bonding structure
AU - Kondo, Masataka
AU - Koita, Taketoshi
AU - Lim, Soowon
AU - Namihira, Takao
AU - Tokoro, Chiharu
N1 - Funding Information:
This paragraph of the first footnote will contain the date on which we submitted our paper for review. This work was supported by JST-Mirai Program Grant Number JPMJMI19Ct, Japan.
Funding Information:
This work was supported by the JST-Mirai Program Grant Number JPMJMI19C7, Japan. Part of this work was performed at the project research of Development of Innovative Separation Technology for integrated circular production at Waseda Research Institute for Science, Waseda University.
Funding Information:
ACKNOWLEDGMENT This work was supported by the JST-Mirai Program Grant Number JPMJMI19C7, Japan. Part of this work was performed at the project research of Development of Innovative Separation Technology for integrated circular production at Waseda Research Institute for Science, Waseda University.
Publisher Copyright:
© 2021 IEEE.
PY - 2021
Y1 - 2021
N2 - Recently, the easy disassembly of bonding structures used in lightweight automobile bodies is needed. This is because these bonding structures are difficult to separate efficiently as there are joints using chemicals with a high adhesive strength and are commonly separated manually. In this study, we applied a pulsed discharge for the separation of bonding structures consisting of two adherends bonded by epoxy adhesive. The separation was carried out by controlling the discharge path inside the adhesive with a notch punched on the adherend and peeling the adhesive by the explosive force caused by the discharge. The discharge path in the adhesive was generated by the concentration of electric field at the tip of the notch. The effect of notch geometry on the electric field strength was studied by simulation with the AC/DC module of COMSOL Multiphysics. Simulation results indicated that the notch height affected the electric field concentration, and likewise, that the electric field strength at the notch was higher than the one at the edge of the adhered material. The discharge path of the bonding structure with the notch was visualized using the shadowgraph method. The fracture surfaces of structure without and with the notch after the pulsed discharge were also observed to confirm the discharge crater. The visualized images indicated that the discharge path occurred inside the adhesive from the tip of the notch and that the structure was separated by the expansion of gasified adhesive caused by the discharge when the notch was punched to the structure. A discharge crater was observed in the adhesive surface near the notch. In the case of the structure without a notch, the discharge luminescence appeared not in the adhesive but at the edge of the adherend because of the electric field concentration at the edge, resulting in non-separation due to surface discharge in the structure. These results indicated that the notch was responsible for controlling the discharge path inside the adhesive and caused the separation of the bonding structure.
AB - Recently, the easy disassembly of bonding structures used in lightweight automobile bodies is needed. This is because these bonding structures are difficult to separate efficiently as there are joints using chemicals with a high adhesive strength and are commonly separated manually. In this study, we applied a pulsed discharge for the separation of bonding structures consisting of two adherends bonded by epoxy adhesive. The separation was carried out by controlling the discharge path inside the adhesive with a notch punched on the adherend and peeling the adhesive by the explosive force caused by the discharge. The discharge path in the adhesive was generated by the concentration of electric field at the tip of the notch. The effect of notch geometry on the electric field strength was studied by simulation with the AC/DC module of COMSOL Multiphysics. Simulation results indicated that the notch height affected the electric field concentration, and likewise, that the electric field strength at the notch was higher than the one at the edge of the adhered material. The discharge path of the bonding structure with the notch was visualized using the shadowgraph method. The fracture surfaces of structure without and with the notch after the pulsed discharge were also observed to confirm the discharge crater. The visualized images indicated that the discharge path occurred inside the adhesive from the tip of the notch and that the structure was separated by the expansion of gasified adhesive caused by the discharge when the notch was punched to the structure. A discharge crater was observed in the adhesive surface near the notch. In the case of the structure without a notch, the discharge luminescence appeared not in the adhesive but at the edge of the adherend because of the electric field concentration at the edge, resulting in non-separation due to surface discharge in the structure. These results indicated that the notch was responsible for controlling the discharge path inside the adhesive and caused the separation of the bonding structure.
KW - Bonding structure
KW - Electric field
KW - Notch
KW - Pulsed discharge
KW - Separation
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U2 - 10.1109/PPC40517.2021.9733147
DO - 10.1109/PPC40517.2021.9733147
M3 - Conference contribution
AN - SCOPUS:85127221746
T3 - IEEE International Pulsed Power Conference
BT - 2021 IEEE Pulsed Power Conference, PPC 2021
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2021 IEEE Pulsed Power Conference, PPC 2021
Y2 - 12 December 2021 through 16 December 2021
ER -